重点讲解：
1. be associated with
（与…）相关的；相联系的；
eg. Hell is traditionally associated with suffering.
地狱历来与受苦联系在一起。
eg. Orange-blossom is associated with weddings.
看到橙花可以使人联想到婚礼。
2. on average
平均起来；按平均值；
eg. On average, I spend 100 on books each month.
我平均每个月花在买书的钱有100元。
eg. London has on average 7.6 hours of sunshine per day during May.
伦敦五月份每天平均有7.6小时日照时间。
3. turn on
打开（设备）；接通（…的供应）；
eg. Parents can programme the machine not to turn on at certain times.
父母可以设定这台机器的程序，使它在特定时间段无法开启。
eg. He forgot to turn on the radio and thus missed the program.
他忘了打开收音机，因此错过了那个节目。
4. discharge from
允许…离开（医院、军队）；
eg. I don't think you should discharge from hospital so early.
我认为你不应该这么早出院。
eg. The pupils were discharged from school.
小学生们放学了
